I am thinking maybe the burden of knowing you are selling a lie to the world is the cause of most wrestlers mental illness, which later lead to them committing suicide. Most of the wrestlers who tragically killed themselves had drug problems.
Below is a list of to popular wrestlers who committed suicide.

The youngest of the Von Erich boys; Chris committed suicide in 1991. If you grew up in the 80s and watched a lot of television like me, you would definitely know about the Von Erich family. There father, Fritz Von Erich was a wrestler in the 50s/60s, and his sons took after him in the 80s to become big professional wrestlers. Their real surname was Adkisson, but they adopted the Von Erich last name for wrestling.
Chris was the smallest of the Von Erich brothers (Chris, Mike, David, Jerry, and Kevin), and was asthmatic. His bones were not strong and he would often break them while performing wrestling maneuvers. This and other issues led him to a life of drugs. Chris Von Erich shot himself in the head on September 12, 1991, three weeks before his 22nd birthday.